This was an IT issue with load balancers. This has been resolved.
Posted 8 months ago. Oct 03, 2017 - 12:26 CDT
When "Allow User to Edit Data After Submission" is not checked, users are getting redirect errors on commerce forms if back is clicked from the billing page - has been identified as a Severity 1 Blocker Defect and will be reviewed and fixed by our development team as soon as possible. The ticket number for your reference is ENC-29920. This ticket has been re-opened to address this issue that is still affecting standard commerce forms only.
Posted 8 months ago. Oct 03, 2017 - 11:11 CDT
This incident affected: In Application Issues - Severity 1 Defects.